Automatic gun selector



1944- s. w. PONTIUS an 2,355,179

AUTOMATIC GUN SELECTOR Filed Feb. 20, 1940 4 Sheets-Sheet 1 INVEN TOR.

GEORGE W. 'Pown v6 Aug. 8, 1944. s. w. PONTIUS 3D AUTOMATIC GUN SELECTOR Filed Feb. 20, 1940 4 Sheets-Sheet 2 INVENTOR. GEQEGE W. @ormus 11: BY

III/I/I/l/A 1944- G. w. PONTIUS 30 2,355,179

AUTOMATIC GUN SELECTOR Filed Feb. 20, 1940 4 Shee'ts-Sheet 3 /:?0 l fi 2'8 28 lzz U, /!6 $2 I INVENTOR. GEOBGE W 'DONTI 05 Aug. 8, 1944.

G. W. PONTIUS 3D AUTOMATIC GUN SELECTOR Filed Feb. 20, 1940 4 sheets-sheep 4 INVENTOR. GEORGE W. 'Dormus 1113 BY Patented Aug. 8, 1944 AUTOMATIC GUN SELECTOR George W. Pontius, III, South Bend, Ind., assignor to Bendix Aviation Corporation, South Bend, 1nd., a corporation o! Delaware Application February 20, 1940, Serial No. 319,925

8 Claims.

This invention relates to charging mechanisms for guns. More particularly, it relates to a selector mechanism for charging one or several of a battery of guns having a common charging control. Also it relates to means for indicatin the necessity for charging a gun.

The invention is shown as applied to machine guns which are mounted in an airplane, although it is equally applicable to any type of gun charged from a remote source. It is customary in current military practice to increase the fire power of a fighting airplane. One mode of increasing this fire power is to mount guns in batteries at suitable points on an airplane and control the aim and firing from a common or central control point. Another device used to increase fire power is to mount guns in the wings of an airplane and aim them by pointing the airplane at the target. In either case, the person controlling the fire of the guns must do so by remote control. Further, to

simplify the tasks of the gunner and save weight, a

there must be a minimum of controls forsuch guns.

Charging guns by power means is now common to save the operator the strenuous manual effort required by the high caliber guns in common usage. Charging a machine gun is necessary when a dud shell is inserted in the mechanism or when the machine gun otherwise Jambs. The operation of charging inserts a fresh shell into the gun and prepares the gun for further automatic firing. The charging means may be hydraulic, such as that described in my joint, copending application, Serial No. 311,978, filed January 2, 1940, on behalf of White and Pontius, or may be pneumatic or electric or some power medium. A single control for a battery of charging mechanisms may be located in the gunner's cockpit.

When an indicating means shows that one gun is not firing it would not be desirable to charge all the guns common to the one control. Rather, it is desirable that the operating guns continue fire and that the jambed guns alone be charged. My invention relates to means to select the gun or guns of a battery of guns which is centrally controlled, and charge the inoperative guns alone without interfering with the operation of the others. Also my invention relates to means which indicate that a gun is in need of charging.

It is therefore an object of my invention to provide means to indicate the necessity of charging a gun.

It is also an object to provide an automatic selector which will allow charging of a jambed jects and advantages of the invention will be apparent in the following description and claims, which may best be understood when considered in conjunction with the accompanying drawings in which:

Figure 1 is a plan view of an airplane equipped with several batteries'of machine guns;

Figure 2 is a sectional view of a dashpot switch used'to indicate an'inoperative gun and to operate the selector means;

Figure 3 is a sectional View of a hydraulic valve used in conjunction with a hydraulic charger, and showing'a' pressure switch attached;

Figure 4 is; a diagrammatic layout of the electrical and hydraulic controls for the machine gun batteries shown in Figure 1; and

Figure 5 is a side view of a machine gun equipped with the invention in an alternative hookup.

. for the rear gunner. On the rear of cockpit i4 is gun without charging operating guns. Other ob- 55 a dashboard l6, mounting a plurality of hydraulic charging valves l8 and indicating lights 20 directly below these valves. The valves l8 are of the type wherein pressure build-up at the end of a charging stroke causes the valve to shut off the pressure supply and to connect the charging mechanism to exhaust, as fully described in application Ser, No. 311,978 mentioned above. Two gun batteries of machine guns are mounted on the airplane in turrets 22, one at the tail, one at the rear of each motor, and one directly behind cockpit l4. These turrets 22 are aimed and fired by the gunner in cockpit H by a control stick 24 retaining a trigger switch 26.

Each gun 28 of a battery has a dashpot switch 30, shown in Figure 2. The switch 30 is mounted at the rear extremity of the breech bolt travel, and is operated by the breech pin 32. A bracket 34 is mounted on gun 28, and retains a cylinder 36. An axially drilled bushing 38 is threaded into the bottom of cylinder 36. A piston rod 40 rides in bushing 38 and has a piston 42 secured to its upper end by a nut. The piston 42 has bleed holes 45 through it. The lower end of piston rod 40 is slotted. A crank M is pivoted to bracket 34 at 46 and when one end is struck by breech pin 32, the other end acts through the slot in piston rod III to draw piston 42 downward. This crank 44 may be a spring member to absorb the shock 01 breech pin contact. A spring 18 urges piston 42 upward. The cylinder 36 is closed on top by an insulator pressures.

cap threaded into it, which retains a conductor 02 attached to a wire I24.

When trigger switch 20 is closed, besides actuating a trigger mechanism, current charges wire I24. If the gun fires, breech bolt 32 will reciprocate with each shot, kicking crank and pulling piston 42 downward. Between reciprocations. spring 40 pushes piston 42 upward, compressing air in the upper'part. The passages 40 meter the air and give a definite period of time for the complete upward stroke of the piston. This period of time is greater than the time between reciprocations of breech pin 32. Should a defective cartridge be inserted into the firing chamber of the gun, or the gun become jambed, piston 42 would go to the top, and piston rod 40 touches contact 02, grounding the electric current of wire I24 through cylinder 36 and bracket 34. The current fiow thus established passes through a solenoid in series. opening a hydraulic valve or operating other controls actuating a charging mechanism. I

A solenoid valve 50 operated by dash-pot 30 shown in Figure 3. Fluid under pressure controlled by charger valve l0, fiows through tube 60 and eventually into the hydraulic charging mechanism 02 which is attached to the side of machine guns 28. The valve consists of a casing 64, having a valve seat 06 mounted therein. A ball 60 held in a steel rod 10 closes of! passage through the valve seat 66. The valve rod 10 slides loosely in a casing 12 threaded into casing 64 against an annular packing ring 14. A spring 10 biases valve rod 10 toward valve seat 60. A steel ring 10 fits over casing 12, and a solenoid 00 is placed over it. Solenoid 00 is encased in a steel shell 82, tightened by nut 04 against annular packing ring 06 inserted in casing 04.

When dashpot 30 closes the circuit and energizes solenoid 80 to open valve 00, the passage is open to the charger 02 for high pressure fluid.

Should the gunner now open charger valve l0, high pressure fluid would enter charger 82 and retract the breech bolt of gun to reload it. However, it will be seen from examination of Figure 2 that the crank 44 is a short distance along the path of reciprocation of breech pin 32 when electrical contact is made. The breech pin 32 strikes the crank 44 at a point where breech pin 32 is. shown by a broken circle. If electrical contact is broken at this instant, solenoid 80 will be deenergized and spring 10 will close the valve 00 stopping further charging action. To eliminate this difiiculty, electrical contact must be maintained until the charging stroke is completed. This function is performed by a pressure responsive switch 00, which acts as an additional ground for solenoid 00, responsive to charger A casing 02 is threaded into casing 04 posterior to valve seat 00. A flexible diaphragm 94 presses a resilient conductor against contact 98 held in an insulator cap I00. Resilient conductor 96 is attached to casing 92, and is thereby effectively grounded.

Fluid under pressure enterscasing 02 and hydraulic valves I3 have a pressure connection H0 and an exhaust line 2 with a cylinder line II4 leading to the chargers 02 on the machine guns 20. Hydraulic fluid fiows through valve 00 and into the charging mechanism 02. When the charging operation is finished, valve I0 opens to exhaust and the fiuid fiows back through line I I4 through valve I0 to exhaust line II2.

The electrical circuits are of the single line type. A source of potential and current I20 is grounded at one end to the metal frame of the aircraft. The other outlet is connected to a feed wire I22 having the gunners switch 20 in series with it. Feed wire I22 has four branches I24 leading to the gun turrets, one each for each turret. These lines lead to solenoids 00 which are in series, and the lines are grounded at either dashpot switch 30 or pressure switch 90. When either ground circuit is completed, current flows through lines I24, energizing solenoids 00 and opening valves 58 to charging fluid. An indicator line I30 connects feed line I22 with the switches to ground through an indicating light 20 in series. Whenever dashpot switch 30 closes, current will flow through line I30 lighting indicator 20, as well as through line I24 operating solenoid 80. It is obvious that light 20 could be in parallel with a resistance in line I24 near line I22, eliminating the long wire I30 in Figure 4.

In operation, referring to Figure 1, the gunner is in cockpit I4 facing backward. Upon detecting a target within range, he grasps control stick 24 and points all the turrets 22 at the target. When the sighting mechanism indicates that the target is in the line of fire, the gunner closes switch 28, which fires the guns. If a dud should be inserted in a gun by the automatic loading mechanism, it would not tire, and since recoil reloads a gun, the gun will remain in an inoperative condition.

During firing, the breech pin 32 on the breech bolt, as shown in Figure 2, will strike crank 44, pulling piston 42 downward. But if the gun should cease firing, as when a dud is in the breech, the spring 40 will force piston 42 upward, making contact with 52 and grounding line I24. This causes current to ilow through solenoid 00, as shown in Figure 4. The solenoid causes valve rod 10 to lift off of valve seat 00, shown in Figure 3, and passage to gun charger 62 is now open.

The closing of dashpot switch 30 also causes current to flow through light 20, indicating to the gunner that one of the guns of a turret is not firing. The gunner thereupon operates valve I3 controlling the turret oi the respective indicatorlight 20, and fluid under pressure flows through valve 58 into charging mechanism 02. The charging mechanism causes the breech bolt to be moved backward and breech pin 32 to contact .the now extended crank 44 of Figure 2. Upon striking crank 44, the contact of line I24 to ground is broken. However, the solenoid 00 is not deenergized because as soon as fiuid enters charger 62, the pressure upon diaphragm 94 of Figure 3 closes the contact, and a second switch to ground is closed. In this manner current flows through line I24 until the charging stroke is finished,'and the fiuid pressure is reduced automatically by valve I0. At the same instant switch 00 opens, indicator light 20 goes out, indicating that all guns are now in firing condition. By arranging the opening of valve 50 when there is no pressure upon it, a very small and light weight solenoid may be used. It may seem inconvenient to have the gunner fire a test salvo before he can find out whether or not the guns are in operating condition. But only by actually,

is shown in Figure 5. The machine gun 28 is -mounted at the rear in slide support III! and is supported at the forward end by bracket 2I2 acting through recoil mechanism 2. The recoil mechanism may be of any known type, allowing the gun It to bodily recoil a limited distance to absorb the reaction of projectile acceleration. Dashpot switch 30 is mounted to forward support 2I2. .A member 2H5 projects from the hottom of machine gun 28, contacting the piston rod 40 of dashpot switch 30 through a transverse bolt 2I8. It .will be noted that in this installation pressure switch 90 is omitted. v

In operation, the gunner closes trigger switch 28, firing the guns through a mechanism not shown at the same time line I is charged. Up-

on firing, the gun 28 bodily recoils, sliding in rear support 2III, and also sliding in recoil unit 2, which absorbs the shock orprojctile, accele ation. Catch 2I6 moves baclrwardwith the gun, pulling piston rod 40 with lt,breaking the contact to ground of line I2l. Upon return of the gun to firing position, the spring 48, shown in Figure 2, pulls piston rod III inward to make contact with lead 52. If the gun is firing regularly, catch H6 will again contact piston rod 40 before it can ground line I24. However, if the gun should now jamb, due to a dud being inserted or otherwise, firing ceases, stopping recoil, and piston rod 40 contacts lead 52 grounding wire I24. This causes currentto flow through lines I24 and I30, opening solenoid valve 58 and lighting indicator light 20. The gunner thenopens charger valve I8, causing fluid to enter charger 82 through conduit ill and charge gun 28, inserting a fresh shell in the gun. During the charging operation the gun does not recoil, but remains stationary. The trigger mechanism now fires the gun, recoil results and the contact to ground through switch 30 is now broken. Solenoid valve 58 now closes, and indicator light 20 goes out. By using the recoil of the gun, a firing phenomenon, instead of the breech bolt recoil, a charging phenomenon, the necessity of a pressure switch is eliminated. It will be noted that in this embodiment of the invention the switch 30 can be attached to any stationary member or unit.

Although the invention has been described with reference to the electrical control of a hydraulic charger, it is not limited to such specific units. The charging mechanism could be an electrical, magnetic; pneumatic or mechanical servo unit. or other type of unit and still the invention would be applicable. The solenoid 80 would in such'case operate suitable switches, valves or controls necessary to operate the charging mechanism. Nor need the control system be electrical. It could be hydraulic, pneumatic or other type. In place of adashp ot switch, a fluid valve could be substituted, and in place or a solenoid, a fluid motor could be substituted. The indicator mechanism could also be diflerent, such as a mechanical signal, fluid operated or otherwise.

Although the invention has been illustrated and described with reference to a particular emclosure or illustrations or otherwise except by the terms of the following claims.

I claim:

1. In a firing control system for a plurality of automatic guns, a source of hydraulicfluid under pressure, a plurality of hydraulic fluid motors connected to said source and adapted to be associated one with each gun for charging its associated gun in the event of a misfire, a control for 'said motors for selectively communicating the-motors with said pressure source or to atmosphere, an electric circuit adapted to be associated with said guns, a trigger switch in said circuit for firing said guns, solenoid operated valves in said circuit, one of said, valves being positioned intermediate the control and each of said hydraulic fluid motors for, controlling the flow of fluid to the respective motors, and a plurality of means in said circuit one of said means.

adapted to-be associated with each of'said automatic guns and adapted to actuate the solenoid operated valve controlling the flow of fluid to the motors of said one automatic gun upon the misflre of said one automatic gun to permit the fiow of fluid to the hydraulic fiuid motor of said one automatic gun, said means also suited to prevent actuation of said solenoid operated valve associatediwith said one automatic gun to arrest the flow of fluid to said hydraulic fluid motor at times when said one automatic gun is firing, and

means intermediate eachsolenoid operated valve and its associated fluid motor and responsive to the pressure in said motor for insuring the actuation of the solenoid operated valve even after the cessation of operation of the first said means.

2. In a firing control system for a plurality of automatic guns, a source of hydraulic fluid under pressure, a plurality. ofhydraulic fluid motors connected to said source and adapted to be associated one with each gun for charging its associated gun in the event of a misfire, a manual control for said motors'for selectively communicating the motors with ,said pressure source or to atmosphere, an electric circuit adapted to be associated with said guns, a trigger switch in said circuit for firing said guns, solenoid operated valves in said circuit, one of said valves being positioned intermediate the control and each of said hydraulic fluid motors for controlling the flow of fluid to the respective motors, and a plurality of means in said circuit one of said means adapted to be associated with each of said automatic guns and adapted to actuate the solenoid o t v valve controlling the flow of fluid to the motor of said one automatic gun upon the misfire of said automatic gun to permit the flow of fluid to the hydraulic fluid motor of said gun, said means bodiment thereof, it is not limited to the disalso suited to prevent actuation of said solenoid operated valve associated with said one automatic gun to arrest the flow of fluid to said hydraulic fluid motor at times when said one automatic gun is firing, and means intermediate each solenoid operated valve and'its associated fluid motor and responsive to the pressure in said mc-.

tor for insuring the actuation of the solenoid op- I erated valve even after the cessation of operation of the first said means.

3. Ina firing control system for a plurality of automatic guns, a source of hydraulic fluid under pressure, a plurality of hydraulic fluid motors connected to said source and adapted to be a.s-

sociated one with each gun for charging its associated gun in the event of a misfire, a control for said motors for selectively communicating the motors with said pressure source or as, at-' mosphere, an electric circuit adapted to be associated with said guns, a trigger. switchin said circuit for firing said guns, indicating means in said circuit for indicating the misflre 01, a gun,

solenoid operatedvalves in said circuit, one of said valves being positioned intermediate the control and each of said hydraulic fluid motors for ccmtrolling' the flow of fluid to the respective motors, and a'plurality of means in said circuit one of said means adapted to be associated with each of said automatic guns and adapted to actuate the solenoid operated valve controlling the flow of fluid to the motor or said one automatic gun upon the misflre of said automatic gun to permit the flow oi fluid to the hydraulic fluid motor of said gun, said means'also suited to prevent actuation of said solenoid operated valve associated with said one automatic gun to arrest the flow of fluid to said hydraulic fluid motor at times when said one automatic gun is firing, and means intermediate each solenoid operated valve and its associated fluid motor and responsive to the pressure in said motor for insuring the actuation of the solenoid operated valve even after the cessation of operation 01' the flrst said means.

4. In a firing control system for a plurality of automatic guns, a source of hydraulic fluid under pressure, a plurality of hydraulic fluid motors connected to said source and adapted to, be associated one with each gun for charging its asso ciated gun in the event of a misflre, a manual control for said motors for selectively co'mmunieating the motors with said pressure source or to adapted to be associated with each gun and each of said means comprising a dashpot and switch and each means operable upon the misflre of the automatic gun with which said means is associated to close said circuit to actuate the solenoid when said automatic gun is flring, and means intermediate each solenoid operated valve and its associated fluid motor and responsive to the pressure admitted thereto for continuing the actuation of the solenoid operatedvalve even after the dashpot means has ceased operation.

6. In a firing control system i'or a plurality of automatic guns, a source of hydraulic fluid under pressure, a plurality of hydraulic fluid motors connected to said source and adapted to be associated one with each gun for charging its assoelated gunlin the event of a misflre, a manual control ionsaid motors for selectively communicating the motors with said pressure source or to atmosphere, an electric circuit adapted to be associated with said guns, a trigger switch in said circuit 'for flring said guns, solenoid operated ,val'ves in said circuit, onesof said valves being positioned intermediate the control and each of saidyhydraulic fluid motors for controlling the flow o1 fluid to the respective motors, and a plu- 'ralityjof means in said circuit one of said means atmosphere, an electric circuit adapted to be associated with said guns, a trigger switchin said circuit for firing said guns, indicating means in said circuit for indicating the misflre of a gun, solenoid operated valves in said circuit, one of said valves being positioned intermediate the control and each or said hydraulic fluid motors for controlling the flowoi fluid to the respective motors, and 'a plurality of means in said circuit one 01' said means adapted to be assoadapted to be associated with each gun and each .oisaid means comprising a dashpot and switch and ;each means operable upon the misflre of the automatic gun with which said means is associated to close said circuit to actuate the solenoid ciated with .each of said automatic guns and adapted to actuate the-solenoid operated valve controlling the flow of fluid to the motorot said one automatic gun upon the misflre of saidautomatic gun to permit the flow of fluid to the hy-' noid operated valve and its associated fluid mo-- operated valve to permit the unimpeded flow oi fluid to the hydraulic fluid motor of said automatic gun, said means also suited to prevent acassociated fluid motor and responsive to the pressure admitted thereto for continuing the actuation of the solenoid operated valve even after the dashpot means has ceased operation.

' 7. In a firing control system for a plurality of automatic guns, a source of hydraulic fluid under 7 pressure, a plurality of hydraulic fluid motors tor and responsive to the pressure in said motor for insuring the actuation of the solenoid operated valve even after the cessation of operation oi the first said means,

connected to said source and adapted to be associated one with each gun for charging its associated gun in the event of a misflre, a control I for said motors for selectively communicating automatic guns, a source of hydraulic fluid under '1 pressure, a plurality of hydraulic fluid motors connected to said source and adapted to be associated one with each gun for charging its assophere, an electric circuit adapted to be associated withrsaid guns, a trigger switch in said circuit for firing said guns, solenoid operated the motors with said pressure source or to atmosphere, an electric circuit adapted to be assosaid circuit for indicating the misflre of a gun,

solenoid operated valves in said circuit, one of said valves being positioned intermediate the control and each of said hydraulic fluid motors ior controlling the flow of fluid to the respective motors, and a plurality of means in said circuit one of said means adapted to be associated with each gun and each of said means comprising a valves in said circuit, one 0! said valvesbeing 7 positioned intermediate the control and each of said hydraulic fluid motors for controlling the f flow oi fluid to the respective motors, and a pludashpot and switch and each means operable upon the misflre of the automatic gun with which said means is associated to close said circuit to actuate the solenoid operated valve to permit the unimpeded flow of fluid to the hy- ,drauli'c fluid motor of said automatic gun, said meansalso suited to prevent actuation of said solenoid operated valveassociated with said aua tomatic gun to'arrest the now ofvfluid to said,hy'-.

draulic fluidfimotor atutimes when 'saidf-aut'omatic gun is flri pandmeans-intermediate each solenoid operated valve and its associated fluid motor and responsive to the pressureadmitted thereto for continuing the I actuation of the solenoid operated valveevenaft'er thedashpot means has ceased operation. v v

' 8. In a firing controlsystem for a plurality of automatic guns, a source of hydraulic fluid under pressure, aplurality of hydraulic fluid motors connected tojsaid source and adapted to be associated one witheach; gun Ior charging its associated gun in'the event of a misflre, a manualcontrol for said motors for selectively communi T cating the motors'withfsaid pressure source or-to atmosphere, an electric circuit adapted to be as sociated with said'guns, a trigger switch in said circuit for" flring'jsaid guns, indicating means in said circuit for indicating the misflre of a gun,

I solenoid'operated valves in. said circuit; one of I said .valves being positioned intermediate the control and each of saidvhydraulic fluid motors for controlling. the flow offluid "to-the respective motors, and a plurality-of means in said circuit one of said means adapted to be associated with each gun'and each of said means comprising a ciated with said automatic gun to arrest the flow ot .fluid'to said hydraulic fluid motor at times when said automatic gun is'firing, and means intermediate each solenoid operated valve and its associated *fluid motor and responsive to the pressure-admitted thereto forcontinuing the ac tuation of the solenoid operated valve even after thedashpotmeans has ceased operation- GEORGE w POlflfTIUs; III. 

